Method of making mechanical negatives for photocopies



March 11, 1952 v PQTTEIGER 2,588,572

METHOD OF MAKING MECHANICAL NEGATIVES FOR PHOTOCOPIES Filed Sept. 25, 1947 gvwa/wtm R. .v. POTTEIGER Patented Mar. 11, 1952? METHOD F MAKING MECHANICAL NEGA- TIVES FOR PHOTOCOPIES Roy Victor Potteiger, Rochester, N. Y.

Application September 23, 1947, Serial No. 775,610

4 Claims.

This invention relates to a method for producing a matrix from which master plates, matrices, etc. of metal and paper may be prepared for printing, and to means particularly adapted for use in carrying out the method.

The advantages of producing a master by means of a typewriter, or other standard writing means, from which printin plates or matrices may be made long has been recognized Considerable experimental work has been done and a number of patents have issued directed to methods and means for producing this result. Some of the difficulties encountered have led to imperfect results and consequently these methods have not come into general use.

Prior to the present invention, it has been proposed to use a sheet of transparent or translucent material as a base and to make an im pression upon the face of such sheet by means of a typewriter. This would give a ribbon copy, butv due to the fact that a typewriter ribbon is an inked, woven fabric the impression made will have a ragged outline due to the inherent rough texture of the woven ribbon. Further, the impression made upon transparent or translucent material will be of uneven density, being blacker alon the edges than in the center, due to the sharp face of the type causing a spreading of the ink at the center of the line. Frequently, on transparent material the impression will be in the form of a double line, outlining the letter with litle or no ink being deposited between the lines.

To overcome this and obtain a more opaque impression, it was suggested that a sheet of carbon paper be placed against the reverse side of the material when the material was inserted into a typewriter, so that a ribbon impression could be made upon the face and a carbon impression on the under side. Thus, on transparent or translucent material, the visual impression was a composite one made up of the ribbon and carbon impressions. The impression thus made is more opaque it is true, but as the impressions made by the ribbon and carbon are of unequal width the composite impression will have a shadowy, indefinite outline. Furthermore, as the ribbon impression will be of uneven density, the opacity of the composite impression will be uneven. When impressions are made upon both sides of the sheet, it is impossible to permit either side of the typed master to touch a foreign object without danger of smearing or smudging the impression upon one side or the other, which will further blur the outline and reduce the opacity of the printed matter.

The object of the present invention is to provide a method whereby a matrix may be formed on transparent material by the use of a conventional, mechanical writing machine, the printed letters on the matrix being of clean cut outline Lsmudging.

and perfectly opaque from edge to edge, and the matrix being suitable for use in producing an etched master for any type reproduction through manual, mechanical, electronic, chemical, or other means.

Another object of the invention is to provide such a method whereby the matrix produced will protect the printed impression to prevent smudging by contact with foreign objects.

A further object of the invention is to provide a method for producing a matrix wherein a plurality of impressions are made, the plural impressions being maintained in perfect registry to increase the opacity of the impression and preserve a sharp outline.

Still another object of the invention is to pro vide means particularly adapted for carrying out the method.

Other objects of the invention will become apparent from the following detailed description when taken in conjunction with the drawings which accompany and form a part of this specification.

In the drawings:

Figure 1 is a perspective view of a pair of superimposed, transparent sheets with carbon or other impression means interposed therebetween; and

Figure 2 is a perspective view of a completed matrix made in accordance with the present invention.

The present invention is concerned with the creation of sharp outlined, perfectly opaque letters upon material of maximum transparency to form a matrix from which printing masters may be obtained. To this end, it is proposed to produce by the use of any standard mechanical writing means plural impressions simultaneously made by identical impression means, with the impressions in registry and protected a ainst Therefore, several sheets of transparent material are used with impression material placed between the sheets. Although the inventive concept is not limited to the number of sheets employed, so long as transparency of the material is not sacrificed, it has been found that employing two sheets and forming impressions on each sheet will give satisfactory opacity to the letters; and, at the same time, maximum transparency is maintained.

Referring to the drawings in detail, there is shown in Figure 1 two superimposed sheets of any suitable transparent material I and 2, joined together along the top edges by means of staples 3. Any type fastening means may be employed, such as mechanical, heat, or adhesive along the edges, so long as it will maintain the sheets in registry. Obviously, a single sheet folded upon itself will accomplish the same purpose. If desired, the sheets also may be secured together along one side edge, to give additional protection against the sheets moving with respect to one another; but at least two edges should be left open to facilitate the insertion of the impression material between the transparent sheets.

In carrying out the method, the transparent sheet i and 2 are separated and two sheets of impression material such as carbon, hectograph, or the like are inserted between the sheets i and 2, the sheets of impression material being oppositely positioned with respect to one another so that the impression side of each is outwardly directed. In other Words, the impression side of sheet 4 will be downward in contact with the upper face of the transparent sheet 2 and the impression side of the sheet 5 will be upward in contact with the underside of the transparent sheet I. Of course, a double-sided carbon, or a single sheet having carbon upon both sides may b substituted for the sheets l and 5. The manifolded sheets are then placed in a typewriter and the desired material is typed thereom For this purpose, the typewriter will have its ribbon removed so that the type bars will strike directly against the upper transparent sheet i. In this manner,

an impression will be made on the underside of transparent sheet I and at the same tim a second impression will be made on the upper side of transparent sheet 2. When the impression material is removed, the two impressions will be in absolute registry, due to the fact that'they are formed on the interfaces of sheets I and 2, As the two impressions are exactly co-incident and in surface contact, only a single impression will be seen, even if the sheet is tilted and the impression viewed from an angle. In other words, the thickness of the transparent sheets will in no way disturb the registry of the impression, as this thickness does not separate the impressions. As both impressions are made by means of the carbon Or other sheet and these impressions are made simultaneously with no extra sheets between the carbons, the impressions will be identical in size and weight.

After the typing is finished and the sheets removed from the typewriter, the impression material is withdrawn from between the sheet i and 2 and the opposite ends of the sheets fastened together by means of staples 6. If desired, all of the open sides may be so secured together. This will prevent sliding of the sheets relative to one another and hold the sheets in perfect registry, thus preventing smudging of the impressions.

The matrix so produced has a sharp outline, is perfectly opaque and cannot be damaged by contact with other objects. Through the use of light, or any other reproductive means, commercially practical, etched printing masters may be obtained from such matrices.

It is to be understood that the carrying out of the method i not limited to the use of a typewriter, as any other type of machine may be used, such as addressograph, stencil machines, or other known devices. This method is ideally adapted to the making of matrices of hand drawings, cuts, etc. for use in advertising and the like.

While I have in the above disclosed what is believed to be one practical embodiment of the invention, it is to be understood that various changes may be made by thOSe skilled in the art without departing from the scope of the appended claims.

What is claimed is:

1. A method for producing matrices from which printing masters may be made comprising, inserting sheets having transferable deposit material thereon between superposed plies of flexible light penetrable material with the deposit material contacting the interfaces of the superposed plies, impressing copy upon the outer face of the top ply of the manifolded pile whereby congruent deposits of the transferable material will be made upon the interfaces of the superposed plies, and maintaining the superposed pliesin registry during and after the impression.

2. A method for producing matrices from which printing master may be made comprising, inserting sheets having transferable deposit material thereon between superposed plies of flexible light penetrable material with the deposit material contacting the interfaces of the superposed plies, impressing copy upon the outer face of the top ply of the manifolded pile whereby congruent deposits of the transferable material will be made upon the interface of the superposed plies, removing the sheets having transferable deposit material thereon, and maintaining the superposed plies in registry during and after the impression.

3. A method for producing matrices from which printing masters may be made comprising, inserting sheets having transferable deposit material on one face thereof in back to back relation between superposed plies of flexible light penetrable material with the deposit material contacting the interfaces of the superposed plies, impressing copy upon the outer face of the top ply of the manifolded pile whereby congruent deposits of the transferable material will be made upon the interfaces of the superposed plies, removing the sheets having transferable deposit material thereon, and maintaining the superposed plies in registry during and after the impression.

4. A method for producing matrices from which printing masters may be made comprising, arranging a plurality of plies of flexible light penetrable material in superposed relation, joining the superposed plies along at least one edge thereof, inserting sheets of transferable deposit material thereon between the superposed plies with the deposit material contacting the interfaces of the superposed plies, impressing copy upon the outer face of the top ply of the manifolded pile whereby congruent deposits of the transferable material will be made upon the interfaces of the superposed plies, and removing the sheets having transferable deposit material thereon.

ROY VICTOR POTTEIGER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 345,220 Duval July 6, 1886 642,270 Smith Jan. 20, 1900 729,803 St. John June 2, 1903 799,609 Ludwig Sept. 12, 1905 1,781,902 Gill Nov. 18, 1930 1,917,370 Hickman July 11, 1933 2,275,579 Yanes Mar. 10, 1942 2,386,872 Lewis Got. 16, 1945 

